US4715376A - Isolation of gas in hydraulic spark gap shock wave generator - Google Patents
Isolation of gas in hydraulic spark gap shock wave generator Download PDFInfo
- Publication number
- US4715376A US4715376A US06/928,805 US92880586A US4715376A US 4715376 A US4715376 A US 4715376A US 92880586 A US92880586 A US 92880586A US 4715376 A US4715376 A US 4715376A
- Authority
- US
- United States
- Prior art keywords
- reflector
- spark gap
- liquid
- spark
- diaphram
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
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Classifications
-
- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/18—Methods or devices for transmitting, conducting or directing sound
- G10K11/26—Sound-focusing or directing, e.g. scanning
- G10K11/28—Sound-focusing or directing, e.g. scanning using reflection, e.g. parabolic reflectors
-
- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/02—Mechanical acoustic impedances; Impedance matching, e.g. by horns; Acoustic resonators
-
- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K15/00—Acoustics not otherwise provided for
- G10K15/04—Sound-producing devices
- G10K15/06—Sound-producing devices using electric discharge
Definitions
- Kidney stones, and also naturally-occurring stones in the bladder and the ureter can be extremelyly painful, and often require surgical relief. Excision or destruction of stones in the bladder and sometimes in the ureter can be relatively easily accomplished, but removal of stones from the kidney is a major procedure.
- kidney Removal of stones from the kidney is a very serious and traumatic surgical procedure. A large incision is made in the body. The kidney is essentially removed from the body and cut open. The stone or stones are then removed, whereupon the kidney is sutured and returned to the body, with the body then being sutured. Various efforts have been made to destroy or disintegrate kidney stones so that they can be excreted with the urine.
- Chemotherapy is available as a non-invasive therapy for uric acid stones.
- the urine is alkalyzed, and the stone is dissolved over a substantial period of time. This requires detection of the stone before an acute phase is reached.
- the next step was the use of ultrasound or an electrohydraulic shock wave produced by discharging a capacitor across a spark gap under water or other suitable liquid.
- ultrasound or an electrohydraulic shock wave produced by discharging a capacitor across a spark gap under water or other suitable liquid.
- a reflector which is a portion of an ellipsoid.
- the spark gap is located at the first focus point of the ellipsoid, and the ellipsoid is positioned relative to the body so that the kidney stone or other calculus or concretion is at the second focus point of the ellipsoid.
- the reflector is filled with water. Discharge of a spark across the gap causes rapid vaporization of a portion of the water, and resultant generation of a shock wave which is focused by the reflector on the kidney stone.
- the shock wave travels through the water in the ellipsoidal reflector, and through the human tissues to the kidney stone. A repetition of the spark gap shock wave generation over a period of perhaps an hour, is necessary to destroy a kidney stone.
- an upwardly directed, truncated ellipsoidal reflector having the upper end covered with a flexible diaphragm of elastomeric of plastic resin material.
- the reflector is filled with water.
- a spark gap is provided at the first focus point of the reflector, and a spark generated across the gap causes vaporization of water to generate a shock wave.
- the spark gap structure including the gap is surrounded by a thin wall cylindrical tube through which fresh water is constantly circulated. Gas released from the water by spark generation thus is continually flushed out of the tube, and is totally isolated from most of the water in the ellipsoidal reflector.
- a thin diaphragm is disposed above the spark gap structure, thereby isolating the apex portion of the ellipsoidal reflector.
- a constant flow of fresh water through the isolated portion of the reflector removes gas from the vicinity of the spark gap mechanism. Gas is totally isolated from the major portion of the water in the reflector.
- FIG. 1 is a longitudinal sectional view of the structure incorporating the first embodiment of the present invention
- FIG. 2 is a view similar to FIG. 1 showing the second embodiment of the present invention.
- FIG. 3 is a perspective view of a portion of the structure of FIG. 2.
- a metal base or block 10 having a hollow interior in the form of a truncated ellipsoidal reflector 12.
- a flexible diaphragm 14 is secured across the open top of the reflector 12 by any suitable means (not shown).
- the diaphragm is waterproof as well as flexible, and preferably is made of an elastomeric or plastic resin material.
- the apex 16 of the reflector is at the bottom thereof, and it is intended that the upwardly opening reflector should be positioned beneath a patient with the diaphragm 14 pressing across the patient's back. This allows ready access to the kidneys, and specifically permits positioning of the second focus point (not shown) of the reflector precisely at the kidney stone to be destroyed.
- the reflector 12 is completely filled with water, and causes the diaphragm 14 to bulge upwardly slightly as shown.
- a thin-walled plastic tube 18 extends through the base 10 transversely of the axis of the reflector 12 and includes the first focus point of the ellipsoid as will be mentioned shortly hereinafter.
- Plastic or other insulating plugs 20 and 22 are provided at the opposite ends of the tube 18 and wedge the tube in corresponding bores 24 and 26 in the body 10.
- Electrodes 28 and 30 extend longitudinally through the blocks 20 and 22 and longitudinally through the tube 18 to close proximity to one another, defining a spark gap 32 therebetween.
- the electrodes extend outwardly from the plugs 20 and 22 and are connected by means such as wires 34 and 36 to a spark generator 38.
- a pipe or conduit 40 extends into a bore 42 in the plug 22, and a pump 44 in the pipe 40 circulates water into the tube 18.
- a complementary bore 46 exhausts water from the tube 18 into a drain pipe 48. Water is thus circulated constantly through the tube 18.
- the tube may be rather limp and is of such a thin wall construction that it might tend to sag, except that the water pressure inside thereof maintains a positive pressure that holds the tube in the erect position shown.
- the spark gap generator is provided with suitable controls (not shown) to charge and discharge a condenser to cause a repetition of sparks across the spark gap 32.
- the spark causes an instantaneous flashing of water in the gap into steam, and thereby generates a shock wave at the first focal point of the ellipsoidal reflector 12.
- the shock waves so generated are focused by the reflector on the kidney stone in the patient, and in due course the kidney stone is reduced to granules or dust which are carried out by the urine without invasion of the patient's body.
- the repeating spark causes a certain amount of gas to be released, which in accordance with the teachings of the prior are would have risen to the underwide of the diaphragm 14, thereby producing an interface that would be a poor transferer of energy.
- the gas that is generated is immediately flushed out of the tube 18 by the constant flow of water therethrough.
- the thin wall of the tube 18 is very resilient and does not interfere in any significant way with transfer of the energy from the spark gap to the kidney stone.
- FIGS. 2 and 3 A modification of the invention is shown in FIGS. 2 and 3. Many of the parts remain as disclosed heretofore, and similar numerals are used for such parts with the addition of the suffix a.
- a horizontal slice is removed from the base or body 10a upwardly a short distance from the apex 16a.
- An insulating ring 50 replaces said slice.
- Bolts 52 extend up through the bottom 54 of the body, through the ring 50, and are threaded into tapped apertures 54 in the upper portion of the body.
- a very thin diaphragm 56 extends across the top of the ring and is clamped against the underside of the upper portion of the body by the ring.
- the outer surface of the ring 50 is conveniently cylindrical as at 58, whereas the inner surface 60 is tapered so as to form a continuation of the surface of the ellipsoidal reflector 12a, whereby not to interfere with the aiming of the shock wave.
- the water supply conduits 42a and 46a extend substantially diametrically through the ring, as do the electrodes 28a and 30a defining the spark gap 32a at the first focus point of the ellipsoidal reflector 12a.
- the diaphragm 56 is sufficiently thin and is made of an elastomeric or plastic resin material as to be rather limp, and is sustained in horizontal position by a slightly greater water pressure below the diaphragm than above it. Gas released by reiterating spark in the gap 32a cannot rise above the diaphragm 56, and is flushed out by the water constantly flowing through the lower portion of the ellipsoidal reflector beneath the diaphragm 56. Consequently, it is not possible for any gas to rise into the water in the major portion of the ellipsoidal reflector and to collect beneath the diaphragm 14a.
- gas generated by a repeating spark in a spark gap to generate a shock wave is prevented from moving very far from the spark gap, and specifically is prevented from rising into the water in the ellipsoidal reflector above the spark gap.
- a constant flow of fresh water flushes such gas out of the space adjacent the spark gap, either in a small tube or beneath a diaphragm spaced only a short distance above the spark gap. Provision of the tube or of the isolating diaphragm does not significantly interfere with the amount of energy transferred from the spark gap to the kidney stone at the second focus point of the ellipsoidal reflector.
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- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Acoustics & Sound (AREA)
- Multimedia (AREA)
- Surgical Instruments (AREA)
Abstract
Description
Claims (2)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US06/928,805 US4715376A (en) | 1986-11-07 | 1986-11-07 | Isolation of gas in hydraulic spark gap shock wave generator |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US06/928,805 US4715376A (en) | 1986-11-07 | 1986-11-07 | Isolation of gas in hydraulic spark gap shock wave generator |
EP87119265A EP0326620A1 (en) | 1987-12-28 | 1987-12-28 | Isolation of gas in hydraulic spark gap shock wave generator |
Publications (1)
Publication Number | Publication Date |
---|---|
US4715376A true US4715376A (en) | 1987-12-29 |
Family
ID=26108881
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US06/928,805 Expired - Fee Related US4715376A (en) | 1986-11-07 | 1986-11-07 | Isolation of gas in hydraulic spark gap shock wave generator |
Country Status (1)
Country | Link |
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US (1) | US4715376A (en) |
Cited By (20)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4813415A (en) * | 1986-08-18 | 1989-03-21 | Siemens Aktiengesellschaft | Sensor for evaluation of shock wave pulses |
EP0322473A1 (en) * | 1987-12-28 | 1989-07-05 | Northgate Research, Inc. a corporation of the state of Illinois | Degassification of water in hydraulic spark gap shock wave generator |
FR2663374A1 (en) * | 1990-06-19 | 1991-12-20 | Technomed Int Sa | METHOD AND DEVICE FOR DECREASING OR ELIMINATING DISTURBANCES CAUSED BY GAS BUBBLES IN COUPLING LIQUID PRESSURE WAVE GENERATORS. |
WO1991019781A1 (en) * | 1990-06-21 | 1991-12-26 | Agracetus, Inc. | Apparatus for genetic transformation |
FR2671239A1 (en) * | 1990-12-26 | 1992-07-03 | Technomed Int Sa | METHOD AND DEVICE INTERPOSING AN ELECTRICALLY CONDUCTIVE LIQUID BETWEEN ELECTRODES AND SHOCK WAVE APPARATUS INCLUDING APPLICATION. |
US5207215A (en) * | 1990-10-29 | 1993-05-04 | Siemens Aktiengesellschaft | Acoustic pressure pulse generator |
US5222483A (en) * | 1991-06-05 | 1993-06-29 | Siemens Aktiengesellschaft | Acoustic pressure pulse generator |
US5251614A (en) * | 1989-06-30 | 1993-10-12 | Technomed International | Method and device interposing an electrically conductive liquid between electrodes and shockwave apparatus for method and device |
US5301169A (en) * | 1989-05-08 | 1994-04-05 | Secretary Of State For Trade And Industry In Her Britannic Majesty's Government Of The United Kingdom Of Great Britain And Northern Ireland | Seismic source |
US5458652A (en) * | 1992-09-28 | 1995-10-17 | Hmt High Medical Technologies Entwicklungs-Und Vertriebs Ag | Device for generating shock waves for non contact disintegration of calculi |
GB2304604A (en) * | 1995-09-01 | 1997-03-26 | Tzn Forschung & Entwicklung | Shock wave generator |
US6080119A (en) * | 1997-05-02 | 2000-06-27 | Hmt Holding Ag | Process and device for generating shock waves for medical uses |
US20080065013A1 (en) * | 2006-09-13 | 2008-03-13 | Boston Scientific Scimed, Inc. | Balloon catheter |
US20160016013A1 (en) * | 2013-03-08 | 2016-01-21 | Soliton, Inc. | Rapid pulse electrohydraulic (eh) shockwave generator apparatus and methods for medical and cosmetic treatments |
US10012063B2 (en) | 2013-03-15 | 2018-07-03 | Chevron U.S.A. Inc. | Ring electrode device and method for generating high-pressure pulses |
US11229575B2 (en) | 2015-05-12 | 2022-01-25 | Soliton, Inc. | Methods of treating cellulite and subcutaneous adipose tissue |
US11794040B2 (en) | 2010-01-19 | 2023-10-24 | The Board Of Regents Of The University Of Texas System | Apparatuses and systems for generating high-frequency shockwaves, and methods of use |
US11813477B2 (en) | 2017-02-19 | 2023-11-14 | Soliton, Inc. | Selective laser induced optical breakdown in biological medium |
US11857212B2 (en) | 2016-07-21 | 2024-01-02 | Soliton, Inc. | Rapid pulse electrohydraulic (EH) shockwave generator apparatus with improved electrode lifetime |
US11865371B2 (en) | 2011-07-15 | 2024-01-09 | The Board of Regents of the University of Texas Syster | Apparatus for generating therapeutic shockwaves and applications of same |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3970076A (en) * | 1974-04-18 | 1976-07-20 | Dornier System Gmbh | Apparatus for heart stimulation |
EP0090138A2 (en) * | 1982-03-25 | 1983-10-05 | DORNIER SYSTEM GmbH | Apparatus for the disintegration of concretions in living bodies |
US4630607A (en) * | 1983-07-19 | 1986-12-23 | N.V. Optische Industrie "De Oude Delft" | Apparatus for the non-contact disintegration of stony objects present in a body by means of sound shockwaves |
-
1986
- 1986-11-07 US US06/928,805 patent/US4715376A/en not_active Expired - Fee Related
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3970076A (en) * | 1974-04-18 | 1976-07-20 | Dornier System Gmbh | Apparatus for heart stimulation |
EP0090138A2 (en) * | 1982-03-25 | 1983-10-05 | DORNIER SYSTEM GmbH | Apparatus for the disintegration of concretions in living bodies |
US4630607A (en) * | 1983-07-19 | 1986-12-23 | N.V. Optische Industrie "De Oude Delft" | Apparatus for the non-contact disintegration of stony objects present in a body by means of sound shockwaves |
Cited By (29)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4813415A (en) * | 1986-08-18 | 1989-03-21 | Siemens Aktiengesellschaft | Sensor for evaluation of shock wave pulses |
EP0322473A1 (en) * | 1987-12-28 | 1989-07-05 | Northgate Research, Inc. a corporation of the state of Illinois | Degassification of water in hydraulic spark gap shock wave generator |
US5301169A (en) * | 1989-05-08 | 1994-04-05 | Secretary Of State For Trade And Industry In Her Britannic Majesty's Government Of The United Kingdom Of Great Britain And Northern Ireland | Seismic source |
US5251614A (en) * | 1989-06-30 | 1993-10-12 | Technomed International | Method and device interposing an electrically conductive liquid between electrodes and shockwave apparatus for method and device |
FR2663374A1 (en) * | 1990-06-19 | 1991-12-20 | Technomed Int Sa | METHOD AND DEVICE FOR DECREASING OR ELIMINATING DISTURBANCES CAUSED BY GAS BUBBLES IN COUPLING LIQUID PRESSURE WAVE GENERATORS. |
WO1991019781A1 (en) * | 1990-06-21 | 1991-12-26 | Agracetus, Inc. | Apparatus for genetic transformation |
US5149655A (en) * | 1990-06-21 | 1992-09-22 | Agracetus, Inc. | Apparatus for genetic transformation |
US5207215A (en) * | 1990-10-29 | 1993-05-04 | Siemens Aktiengesellschaft | Acoustic pressure pulse generator |
FR2671239A1 (en) * | 1990-12-26 | 1992-07-03 | Technomed Int Sa | METHOD AND DEVICE INTERPOSING AN ELECTRICALLY CONDUCTIVE LIQUID BETWEEN ELECTRODES AND SHOCK WAVE APPARATUS INCLUDING APPLICATION. |
WO1992012513A1 (en) * | 1990-12-26 | 1992-07-23 | Technomed International | Method and device for placing a liquid between electrodes in a shock wave apparatus |
US5222483A (en) * | 1991-06-05 | 1993-06-29 | Siemens Aktiengesellschaft | Acoustic pressure pulse generator |
US5458652A (en) * | 1992-09-28 | 1995-10-17 | Hmt High Medical Technologies Entwicklungs-Und Vertriebs Ag | Device for generating shock waves for non contact disintegration of calculi |
GB2304604B (en) * | 1995-09-01 | 1999-11-10 | Tzn Forschung & Entwicklung | Generating high-intensity energy pulses |
GB2304604A (en) * | 1995-09-01 | 1997-03-26 | Tzn Forschung & Entwicklung | Shock wave generator |
US5748563A (en) * | 1995-09-01 | 1998-05-05 | Tzn Forschungs- Und Entwicklungszentrum Unterluss Gmbh | Energy converter for generating high-power pulses |
US6080119A (en) * | 1997-05-02 | 2000-06-27 | Hmt Holding Ag | Process and device for generating shock waves for medical uses |
US20080065013A1 (en) * | 2006-09-13 | 2008-03-13 | Boston Scientific Scimed, Inc. | Balloon catheter |
US11794040B2 (en) | 2010-01-19 | 2023-10-24 | The Board Of Regents Of The University Of Texas System | Apparatuses and systems for generating high-frequency shockwaves, and methods of use |
US11865371B2 (en) | 2011-07-15 | 2024-01-09 | The Board of Regents of the University of Texas Syster | Apparatus for generating therapeutic shockwaves and applications of same |
US20160016013A1 (en) * | 2013-03-08 | 2016-01-21 | Soliton, Inc. | Rapid pulse electrohydraulic (eh) shockwave generator apparatus and methods for medical and cosmetic treatments |
CN110947109A (en) * | 2013-03-08 | 2020-04-03 | 索里顿有限责任公司 | Rapid pulse electrohydraulic shock wave generator device and beauty method |
US10835767B2 (en) | 2013-03-08 | 2020-11-17 | Board Of Regents, The University Of Texas System | Rapid pulse electrohydraulic (EH) shockwave generator apparatus and methods for medical and cosmetic treatments |
US10857393B2 (en) * | 2013-03-08 | 2020-12-08 | Soliton, Inc. | Rapid pulse electrohydraulic (EH) shockwave generator apparatus and methods for medical and cosmetic treatments |
CN110947109B (en) * | 2013-03-08 | 2022-04-26 | 索里顿有限责任公司 | Apparatus for generating therapeutic shock waves |
US10077644B2 (en) | 2013-03-15 | 2018-09-18 | Chevron U.S.A. Inc. | Method and apparatus for generating high-pressure pulses in a subterranean dielectric medium |
US10012063B2 (en) | 2013-03-15 | 2018-07-03 | Chevron U.S.A. Inc. | Ring electrode device and method for generating high-pressure pulses |
US11229575B2 (en) | 2015-05-12 | 2022-01-25 | Soliton, Inc. | Methods of treating cellulite and subcutaneous adipose tissue |
US11857212B2 (en) | 2016-07-21 | 2024-01-02 | Soliton, Inc. | Rapid pulse electrohydraulic (EH) shockwave generator apparatus with improved electrode lifetime |
US11813477B2 (en) | 2017-02-19 | 2023-11-14 | Soliton, Inc. | Selective laser induced optical breakdown in biological medium |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: TRUTEK RESEARCH, INC., 350 TELSER ROAD, LAKE ZURIC Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNORS:NOWACKI, CHRISTOPHER;BRISSON, ALFRED G.;REEL/FRAME:004648/0238 Effective date: 19861104 Owner name: TRUTEK RESEARCH, INC., A CORP OF DE,ILLINOIS Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:NOWACKI, CHRISTOPHER;BRISSON, ALFRED G.;REEL/FRAME:004648/0238 Effective date: 19861104 |
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AS | Assignment |
Owner name: NORTHGATE RESEARCH, INC., 3930 VENTURA DRIVE, SUIT Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:TRUTEK RESEARCH, INC.,;REEL/FRAME:004815/0712 Effective date: 19871113 |
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Year of fee payment: 4 |
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SULP | Surcharge for late payment | ||
REMI | Maintenance fee reminder mailed | ||
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Effective date: 19960103 |
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STCH | Information on status: patent discontinuation |
Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362 |